1. Field of the Invention
The present invention relates to a thin film transistor (TFT), and more particularly, to a TFT that can provide a rectifying function, and electric and optical switching functions of a diode using an n-type CIS (CuInSe2) and a p-type CIS.
2. Description of the Related Art
In general, CIS (CuInSe2), including selenium (Se) which is a chalcogen-based material of group VIB in the periodic table, is classified as a chalcopyrite-based material. CIS has been widely used in solar devices, for example, solar cell devices, due to its high light efficiency. Also, non-energy devices using the CIS has been researched. The non-energy devices have been mainly limited to research into diode devices. For example, the diode devices can be a Schottky-diode or a light sensible diode based on a heterojunction formed of CuSe, which has been recently reported. However, considering the high light efficiency of the CIS, the CIS can be sufficiently applied to a switching device such as a light transistor.